Indirector chlorinator

ABSTRACT

A sewage treatment system particularly adapted for use in small boats, in which an additive for treating the sewage is stored in dry form, such as in tablets, in a tank separate from, but in communication with, the sewage treatment chamber. Flushing a toilet associated with the system automatically activates a water pump and causes water to be pumped from a separate source into the additive tank, dissolve a portion of the additive and flow, such as by gravity, from the tank into the treating chamber. At the same time a combination macerating and mixing unit is energized to reduce solid sewage to at least a maximum particulate size and vigorously mix and remacerate the reduced sewage with the dissolved additive flowing from the tank into the chamber.

United States Patent 1 Russo 1 1 Oct. 2, 1973 [54] INDIRECTORCI-ILORINATOR 3,472,390 10/1969 Pall et al 210/62 6 1970 W'l 75Inventor: Ronald I). Russo, Wethersfield, I X

Conn.

' 1 7 Primary ExaminerSamih N. Zaharna [73] Assignee: Koehler-DaytonInc., New Britian, Assistant E 'rh (1 wi Conn AttorneyJoseph RQ-Spalla1221 Filed: May 5, 1971 21 Appl. No.: 140,574 1571 ABSTRACT Related U SA cation Data A sewage treatment system particularly adapted for use ppin small boats, in which an additive for treating the sew- [63]Contmuatlon-ln-part of Ser. No. 2,101,1an. 12, 1970, age is Stored indry form Such as in tablets, in a tank r' separate from, but incommunication with, the sewage treatment chamber. Flushing a toiletassociated with the system automatically activates a water pump and [58]Fie'ld c 59 causes water to be pumped from a separate source into theadditive tank, dissolve a portion of the additive and I flow, such as bygravity, from the tank into the treating References Cited chamber At thesame time a combination maceratmg and mixing umt 1s energized to reducesolid sewage to UNITED STATES PATENTS at least a maximum particulatesize and vigorously mix 3,451,552 6/1969 Car1son. 210/152 and remaceratethe reduced sewage with the dissolved 3,563,384 2/197l DeLahey additiveflowing from the tank into the chamber. 3,446,356v 5/1969 May 73,463,726 8/1969 Schulte 210/60 X 6 Claims, 2 Drawing Figures INDIRECTORCHLORINATOR CROSS REFERENCE TO RELATED APPLICATION This application is aContinuation-in-Part of application Ser. No. 2,101, filed by applicanton Jan. 12, 1970, for Indirect Chlorinator, now abandoned.

BACKGROUND OF THE INVENTION In order to obviate the pollution problemswhich occur when raw sewage is dumped directly overboard from boats, itis desirable to reduce the solid sewage to an acceptable particulatesize and mix the liquid and reduced solid sewage with a treating agentto lower the bacteria count of the sewage to an acceptable level. Thetreating agent, which may conveniently be a chlorine based additive, ishighly corrosive and difficult to handle in liquid form. To this end,the patent to Carlson, U.S. Pat. No. 3,451,552, issued on June 24, 1967,and the patent to DeLaney et al., U.S. Pat. No. 3,563,384, issued onFeb. 16, 1971, disclose a sewage treatment system for small pleasureboats and the like in which the treating agent is charged into thesystem in a tablet form and the raw sewage, after having been reduced toan acceptable size, is flowed through a bed of the tablets, therebydissolving a portion of the tablets and releasing chlorine to thesystem. The raw sewage, now partially mixed with dissolved chlorine, isdirected from the bed of tablets around a series of baffles to insure athorough mixing and is then directed through a discharge port in thetreatment chamber.

While a system using a bed of tablets through which the raw sewage ispumped does avoid the handling problems associated with highly corrosivesewage treating additives and does serve to reduce the bacteria count ofthe sewage to an acceptable level before it is discharged overboard, thebed of tablets is susceptible to clogging by the solid portion of thesewage, even though this portion is reduced to a relatively smallparticulate size. It should also be noted that the installation ofbaffles in the sewage treating chamber results in additionalmanufacturing time and expense.

Whenever chlorine of high concentration is brought into contact withorganic matter, such as solid human waste or paper products, a chemicalreaction occurs. This results in the formation of a foam or froth insidethe chamber. The reaction is also exothermic which causes undesirablequantities of heat to be generated.

In units such as that disclosed in U.S. Pat. No. 3,451,552, the foamcollects in the tablet bed and holding areas after a few cycles ofoperation and forms a more solid slime or sludge, which restricts thefree flow of water therethrough. As the flow of water is reduced, theheat generated by the chemical reaction is not completely dissipated.Additionally, the slime or sludge may cause a quantity of water to betrapped in the tablet bed between flushings so that the solid tabletsbecome soggy and rapidly consumed on subsequent flushmgs.

SUMMARY OF THE INVENTION A sewage treatment system according to thepresent invention while utilizing a sewage treating additive in a dry,rather than liquid form, maintains the dry additive separate from theraw sewage. When a toilet associated with the sewage system is flushed,a pump is actuated and pumps a relatively uncontaminated solvent, suchas the water in which the boat is floating, into the additive tank,dissolving a portion of the additive and then pass ing into the sewagetreatment chamber. At the same time, a combined macerating and mixingunit is activated, reducing solid materials in the sewage to anacceptable particulate size and then vigorously mixing and remaceratingthe liquid and reduced solid sewage with the dissolved chemical additiveflowing into the chamber.

In this manner the necessity of using a liquid additive is avoided aswell as the problem of clogging associated with a system in which theraw sewage is pumped through a bed of additive in tablet form.

Additionally, by utilizing a vigorous mixer or remacerator inconjunction with the reducing unit, the sewage and the dissolvedadditive are intimately mixed without the necessity of inserting bafflesin sewage treatment chamber.

Furthermore, the foam which is inherently formed by the combining ofconcentrated chlorine and organic matter is broken up or dispersed bythe vigorous mixing or remaceration; and that foam which does remain inthe chamber from a previous usage is washed from the walls of thechamber on the next cycle of operation, thus preventing a buildup ofslime ahd sludge and the concomitant clogging caused thereby.

The above and other features and advantages of the present inventionwill become better understood from the detailed description of theinvention that follows, when considered in connection with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is an elevational view, partlyin cross section, showing a preferred embodiment of the invention; and

FIG. 2 is an elevational view showing a modification of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT As seen in FIG. 1 of thedrawings, the sewage treatment system comprises a chamber 10 having aninlet port 11 and a discharge port 12 formed in opposite walls 13 and 14with at least the discharge port 12 spaced from the bottom wall 15 ofthe chamber.

Positioned in the inlet port 11 is a macerating and mixing device,referenced generally 20, for reducing the particle size andforvigorously agitating the macerated sewage with dissolved additive.The unit 20 comprises a motor 21 which rotates a shaft 22 to which areaffixed a plurality of radially extending blades 23, a substantiallydisk-shaped member 24 and a helical flight 25. The adjacent blades 23have their distal portions directed alternately upwardly and downwardlyand the clearance between the ends of the blades and the substantiallycylindrical wall 26 as well as the distance between the periphery of thedisk 24 and the wall 26 is maintained relatively small for a purpose tobe presently explained.

The helical flight 25, in addition to agitating the contents of thechamber 10, also functions (I) to remacerate the sewage, (2) to break upor disperse the foam formed by the combination of a concentratedadditive, such as chlorine, and organic matter,such as solid human wasteand paper products, and, (3) to flush from the walls 13, 14 and 15 anyfoam remaining from the previous cycle of operation. As to (I), thisfosters the reduction of coliform bacteria, since the chlorine can morereadily contact a greater surface area of the waste material. As to (2),the flight 25 unexpectedly reduces or breaks up the foam, rather thanincreasing it, as would normally result from agitation. Therefore, moreof the foam is dissipated and washed out through the discharge port 12and less slime and sludge is produced in the chamber 10. As to (3), ifthe agitation by the flight 25 is sufficiently intense, the walls of thechamber are actually cleansed of any foam from previous cycles.Therefore, there is little or no buildup of slime or sludge inside thechamber and the clogging caused thereby is avoided.

Mounted on the top wall 16 of the chamber 10 is an additive tank 30containing a supply of sewage treating additive which may be in tabletform, as shown at 31. The top wall 16 also serves as a bottom wall forthe tank 30, and has a series of slots 32 formed therein.

While not forming per se a part of the present invention, the tank 30may also be provided with a sensing mechanism 33 which senses when thelevel of additive in the tank 30 falls below a predetermined amount andprevents actuation of the unit 21 upon this occurrence.

Also mounted on the chamber 10 is a pump 40 having an inlet conduit 41,which may be conveniently directed overboard and thereby provide asource of relatively uncontaminated water to the pump 40, and an outletconduit 42 leading into the tank 30 through the inlet opening 43.

A pressure sensing device of any suitable design, shown schematically inthe drawing at 50, is positioned in the inlet port 11 and is capable ofgenerating a signal to the energizing unit 51 on the sensing of apredetermined pressure in the port 11. The energizing unit 51 is of thetype which incorporates a timing mechanism so that upon generation of asignal to unit 51 the unit will be activated for a preset period oftime. The unit and the pump 40 are connected to the unit 51 by means oflines 53 and 54, respectively, while line 55 connects the safety device33 with the unit 51.

In operation, a charge of raw sewage from a toilet associated with thesewage treatment system is delivered by any convenient means through theinlet port 11 of the chamber 10. This may be accomplished by anautomatic or manual flush system. One conventional form of manuallyoperated pump is one in which the pump handle is actuated a number ofstrokes to draw in water from overboard and force the raw sewage underpressure into the treatment system. If this type of pump is used, thetiming mechanism in unit 51, which may cause the unit to be activated,for example, for a ten second interval upon actuation, allows unit 51 tobe continuously activated as the pump handle is moved up and down,rather than activated on the pressurizing stroke and deactivated on thereturn stroke.

Regardless of the manner in which the sewage is delivered to thechamber, however, the pressure generated is sensed by the pressuresensitive device 50 which generates a signal to control unit 51. Unit 51then energizes the macerating and mixing unit 20 causing the shaft 22 torotate about its axis and subject any solid sewage which passes throughthe inlet port to a reducing action by the blades 23. Due to therelatively small clearance between the outer periphery of the disk 24and the inner surface of the substantially cylindrical member 26, solidsewage is retained in the member 26 until such time as the sewage isreduced to a small enough size to pass between the space between thedisk 24 and the wall 26.

Simultaneously with the energization of the unit 20, the control unit 51energizes the pump 40 causing a supply of relatively uncontaminatedwater to be drawn from any convenient source, such as overboard, throughthe conduits 41 and 42 and the inlet opening 43 to the interior of theadditive tank 30. The solvent passing through the tank 30 causes aportion of the dry additive to be dissolved and pass in liquid formthrough the openings 32 into the chamber 10. The helical flight 25agitates the contents of the chamber and achieves an intermixing of thedissolved additive and the liquid and reduced solid sewage.Additionally, the flight 25 remacerates the sewage, breaks up the foamformed in the chamber 10, and flushes the walls of the chamber 10. Asnoted above, the timing mechanism incorporated in unit 51 allows theunit 51, and hence the motor 21 and pump 40, to operate continuouslyduring pumping of sewage into the chamber rather than intermittently. Asthe liquid level of the combined additive and sewage rises above thelowermost portion of the outlet port 12, the now-treated sewage isdischarged overboard.

In the system described the unit 20 and pump 40 will ordinarily besimultaneously deactivated a preset time interval after the pressure ininlet conduit 11 drops below a predetermined value. Alternatively, aseparate timer can be associated with the pump 40 so that additionaldisinfectant is delivered to chamber 10 after unit 21 is deactivated.

While in the embodiment of FIG. 1 a helical flight 25 is utilized tomacerate and mix the sewage and dissolved additive, it will be notedthat a double bladed macerating and mixing unit may be used as shown inFIG. 2. Thus, as seen in FIG. 2, the unit 20' is equipped with radiallyextending blades 23' mounted above and blades 23" mounted below the disk24' surrounded by the cylindrical wall 26. In this manner the lowerblades 23" not only mix the sewage and additive but also function tofurther reduce sewage particles both before and after the additive andsewage are mixed. As with the helical blade 25, the blades 23" alsobreak up the foam formed in the chamber 10, and flush from the walls ofthe chamber 10 any residue foam from a previous cycle of operation. I

The effectiveness of the instant invention is graphically demonstratedin Table I. These tests were con-.

ducted under applicant's personal supervision at the plant of theassignee of this application. As shown therein the chlorinator of US.Pat. No. 3,451,552 became clogged after a small number of usages. Thisunit did not always clog after only eight uses, but the unit at leastshowed substantial amounts of sludge and slime buildup. This unit usesmuch more chlorine, and, therefore, also discharges more chlorine intothe surrounding water.

The chlorinator of the instant invention without the remacerator 25 or23" showed improved results over the above device, but still had asubstantial problem with foam buildup and the concomitant clogging. Theimprovement undoubtedly was due to passing relatively clean waterthrough the tablet bed in the additive tank 30, rather than passing rawsewage therethrough, as done in the past. A marked improvement in theconsumption of chlorine tablets also results from the use of a meteredamount of relatively clean water. This chlorinator design prevents theraw sewage and water from remaining in contact with the tablets betweenuses, and thereby prevents the tablets from disintegrating as before.

said conduit means including first rotatable impeller means formacerating the effluent and means for restricting the discharge of themacerated effluent therefrom so that only par- The chlorinator of theinstant design utilizing a mac- 5 ticles having a size smaller than apredetermined erator blade 23" completely eliminated the foaming maximumsize may be discharged therefrom, and clogging problems encountered withthe other dea tank containing sewage treatment tablets, gn Th low levelf tablet mp on wa m insecond conduit means for delivering a liquidsubstantained, and at the same time the coliform bacteria in tially freeof particulate material to said tank the effluent were reduced to zero.These were improve- 10 whereby a portion of the sewage treatment tabletsments in kind and not degree. will be dissolved in the liquid,

From the above it will be apparent that the present means fordischarging the liquid including the disinvention obviates the necessityof utilizing difficult to solved portion of the sewage treatment tabletsinto handle liquid sewage treatment additives and at the said sewagetreat-ment chamber wherein the dissame time has eliminated the. problemof clogging assol5 solved portion of the sewage treat-ment tablets willciated with systems in which the raw sewage is circutreat the sewagecontaminants contain e lated through a bed of additive in tablet form orthe second rotatable impeller means located within said like.Additionally, the need for baffling is eliminated, sewerage treatmentchamber for remacerating the with the helical flight 25 and blades 23"serving to intieffluent, and mately intermix thesewage and additi At thSame means mounting said first and second rotatable imtime, the sewagetreatment system of the present inven- Peller means on a common shaftfor conjoint Totation is highly effective in reducing the bacteria countof tionthe sewage and in actual tests the coliform bacteria A system fortreating Sewerage according to Claim count i raw Sewage h b reduced bythe waste 1, wherein said second impeller means comprises a he-[featment System of the present invention to zero 25 lical selectivelyconfigured for directing thfi con- It is to be understood that theinstant invention is not tamed effluent to flush the Sides of Saidtreatment limited to the particular type or shape of blade used inchamberchamber 10 For example i place of the flute 25 and 3. A systemfor treating sewerage according to claim the blades 23" othermacerator-mixers could be used, wherein Said Second impeller meanscomprises a P h as tongs fi or a fl t disc with tabs extending rality ofblades extending radially outwardly from a rotherefrom. Other shapescould also be used. "liable Shaft- While the forms of apparatus hereindescribed con- A system fo treating sewage according to claim 1 stitutepreferred embodiments of the invention, it is to further including motormeans for concurrently enerbe understood that the invention is notlimited to these gizing said first and second impeller means. preciseforms of apparatus, and that changes may be 5. A system for treatingsewage according to claim 1 made therein without departing from thescope of the further comprising third conduit means for discharginginvention which is defined in the appended claims. the treated effluentfrom said sewage treatment chamwhat is claimed is! ber wherein the inletport of said third conduit means TABLE I Chlorinator of type shown inU.S. patent 3,451,552

Ghlorinator of instant invention without remaccrator 25 (Fig.1) or 23(Fig. 2)

Chlorinator of instant invention with rernacerator as shown in Fig. 2

Buildup of foam and sludge.

Collfomi bacteria reduction.

After 8 solid deposits, the device showed less than 240 coliformbacteria per 100 milliliters of effluent.

0.0.1). was reduced to approximately two Chmnionl oxygen thirds ($6) ofthe original untreated demand (C.O.I

Started 11-25-68, test lasted approximately 1 week due to unit showingfoam buildup.

Approximately 20 solid deposits bcforo unit showed serious signs ofclogging.

Approximately 6 tablets were used during a solid deposit flush (cleanwater was directed over the tablets).

Foam began to build up in chamber 10 after approximately the 6th flushand continued until the device began to show excessive accumulation.Although it did not plug the discharge completely. the foam buildupseriously inhibited proper smooth flow through the device.

After 20 solid deposits, the device showed less than 240 coliformbacteria per 100 milliliters of effluent.

0.0. l). was reduced to approximately two thirds (3(1) of the originaluntreated Started 12-9-68, test unit on test for over 3 monthscontinuously.

Over 80 solid deposits and unit showed no sign of foam clogging.

Approximately 6 tablets were used during a solid deposit flush (cleanwater was directed over the tablets).

After continued use by 4 people for an 8 I hour work day in thelaboratory, the device was just as clean as the 1st day. Therelnacerator broke up the foam and sludge and kept the unit clean.

After 80 solid deposits, the device showed zero (0) coliform bacteria inthe efliuent.

C.().l). was reduced to approximately two thirds (9(1) of the originaluntreated reduction. effluent. ofllncnt. ofllncnt. Chlorinccontcnt ofResidual chlorine was very high however, Residual clllorino was reducedsigniflltosldnal chlorine was reduced S t-( vfllucnt. due to excessivedissolving of chlorine cantly due to nsingmncll losschlorino. oantly dueto the unit using less tablets (exceeded 2% chlorine at times).chlorine.

lclaim: is spaced from the bottom of said sewage treatment I. A systemfor treating sewage comprising a sewerage treatment chamber free frombaffles and chamber.

6. A sewage treatment system as recited in claim I,

the like whereby sewage may travel directly from the inlet to the outletthereof,

conduit means for discharging an effluent containing solid sewagecontaminants into said sewage treatment chamber,

wherein: said tank is positioned above said sewage treatment chamber;and the bottom wall of said tank has openings therein communicating withthe said sewage treatment chamber.

1. A system for treating sewage comprising a sewerage treatment chamberfree from baffles and the like whereby sewage may travel directly fromthe inlet to the outlet thereof, conduit means for discharging aneffluent containing solid sewage contaminants into said sewage treatmentchamber, said conduit means including first rotatable impeller means formacerating the effluent and means for restricting the discharge of themacerated effluent therefrom so that only particles having a sizesmaller than a predetermined maximum size may be discharged therefrom, atank containing sewage treatment tablets, second conduit means fordelivering a liquid substantially free of particulate material to saidtank whereby a portion of the sewage treatment tablets will be dissolvedin the liquid, means for discharging the liquid including the dissolvedportion of the sewage treatment tablets into said sewage treat-mentchamber wherein the dissolved portion of the sewage treat-ment tabletswill treat the sewage contaminants contained therein, second rotatableimpeller means located within said sewerage treatment chamber forremacerating the effluent, and means mounting said first and secondrotatable impeller means on a common shaft for conjoint rotation.
 2. Asystem for treating sewerage according to claim 1, wherein said secondimpeller means comprises a helical flight selectively configured fordirecting the contained effluent to flush the sides of said treatmentchamber.
 3. A system for treating sewerage according to claim 1, whereinsaid second impeller means comprises a plurality of blades extendingradially outwardly from a rotatable shaft.
 4. A system for treatingsewage according to claim 1 further including motor means forconcurrently energizing said first and second impeller means.
 5. Asystem for treating sewage according to claim 1 further comprising thirdconduit means for discharging the treated effluent from said sewagetreatment chamber wherein the inlet port of said third conduit means isspaced from the bottom of said sewage treatment chamber.
 6. A sewagetreatment system as recited in claim 1, wherein: said tank is positionedabove said sewage treatment chamber; and the bottom wall of said tankhas openings therein communicating with the said sewage treatmentchamber.